The Assimilation of Amino-acids by Bacteria

SUMMARY: The level of glutamic acid concentration measured inside the streptococcal cell during assimilation represents a balance between the rate at which the amino-acid is withdrawn from the external medium and the rate at which it is metabolized within the cell.

Treatment of the cells, prior to or during assimilation, with dyes of the triphenylmethane series results in raising the level of free glutamic acid attained within the cell. Evidence is presented that the triphenylmethane dyes prevent the metabolism of glutamic acid within the cell. The activity of the triphenylmethane molecule as an antibacterial agent and in raising the level of glutamic acid assimilation is increased by alkyl substitution and can be correlated with the lipid solubility of the dye.